I found this page on www.campingmontana.com, and thought you might enjoy viewing it:
The Campground Owners Association of Montana maintains a website of their current members. The website has the campgrounds split into the six country categories (Missouri River Country, Custer Country, Glacier Country, Yellowstone Country, Russell Country and Gold West Country), as well as all the cities represented by the members of COAM.
You are able to make a tentative reservation with any of the facilities listed on the website simply by filling out an online reservation form.
Check it out!
